A002469 - cp's OEIS frontend

A002469 The game of Mousetrap with n cards: the number of permutations of n cards in which 2 is the only hit.

n	a(n)
2	0
3	0
4	1
5	5
6	31
7	203
8	1501
9	12449
10	114955
11	1171799
12	13082617
13	158860349
14	2085208951
15	29427878435
16	444413828821
17	7151855533913
18	122190894996451
19	2209057440250799
20	42133729714051825
21	845553296311189109
22	17810791160738752207
23	392911423093684031099

[0, 0, 1, 5, 31, 203, 1501, 12449, 114955, 1171799, 13082617, 158860349, 2085208951, 29427878435, 444413828821, 7151855533913, 122190894996451, 2209057440250799, 42133729714051825, 845553296311189109, 17810791160738752207, 392911423093684031099]

cp's OEIS Frontend

A002469 The game of Mousetrap with n cards: the number of permutations of n cards in which 2 is the only hit.

Table of values

List of values